Low
P.03 on Vaillant ecoFIT Pure 435

Your boiler is currently running a specific commissioning test program rather than its normal heating mode.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Check programme for system without eBUS controller.

DIY fix possible

Press the 'Back' button (left arrow) to exit the test program menuTurn the boiler off and back on again at the fused spur switchWait for the boiler to complete its start-up sequence to return to normal operation

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Related fault codes

P.01View →P.02View →P.06View →

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